Chattanooga powers smart grid with a gigabit network

One of the nation’s only gigabit networks is now the communications force behind a new smart grid completed last week in Chattanooga, Tennessee. The utility company EPB installed its last IntelliRupter last Tuesday to finish automating its power distribution network. That means if the community suffers a power outage anywhere, EPB can re-route power automatically to continue the flow of electricity. The utility company isn't the only one getting aggressive with smart grid technology, but it does find itself on the leading edge of communications networks. The same fiber infrastructure that underlies Chattanooga’s heralded gigabit Internet service also drives the region’s utility communications.

Many smart grid applications don’t need the power of fiber. Meter reading, for example, doesn't require the communications network speed that streaming video does. However, when I talked to David Wade, the chief operating officer of EPB last week, he cited a number of reasons for choosing fiber over lower-capacity alternatives. Chattanooga suffered massive outages after a series of tornadoes battered the area last spring. With a fiber network deployed, EPB can now get near-real-time information when a catastrophe like that occurs. Faster info means faster recovery, and faster recovery means less time without the power needed to support emergency response efforts.

On a more mundane level, Wade talked about using the fiber network to deliver a firmware upgrade to EPB’s 1,170 IntelliRupters last week. It took a day and a half to push the update out to every device. In the past, utility workers would have had to drive to each location with a laptop to deliver the new software. That’s a lot of manpower saved.

Speaking of how EPB’s infrastructure has paid off, Wade can also relate some impressive statistics on how the smart grid is saving money for the company and Chattanooga residents. He estimates that the community loses one hundred million dollars annually from power outages. However, with a power network that is now 40%-50% more reliable, that number should go down significantly.

Wade also pointed out that EPB has traditionally overprovisioned its power network because it hasn't had the data on which transformers get overloaded during a demand spike. In fact, Wade says EPB has about 3,000 megawatts of capacity, or installed distribution transformation, but total peak demand only runs up to about 1,300 megawatts. With new analytics on how demand is distributed, EPB will be able to operate more efficiently, upgrading specific transformers only when necessary.

Analytics will help consumers too. Wade noted that EPB in the future could use data, for example, to determine the best time for a hot water heater to draw energy, which the appliance could then store until someone in the household needed hot water. That scenario doesn't involve any inconvenience on the part of consumers, but it would make homes more energy efficient, distributing power usage during a 24-hour cycle to lower peak demand.

EPB presents a strong case for smart grids and gigabit networks, but when I asked Wade, he was emphatic that his primary goal has not been to act as an evangelist for either. His objective has always been to get cheaper and more reliable power to Chattanooga residents. The attention EPB’s efforts have brought to smart utility technologies just happens to be a nice side benefit.